CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - UNAUDITED - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 9,580	$ 9,058	$ 25,309	$ 16,786
Other comprehensive income:
Unrealized holding gains (losses) on securities arising during the period	1,057	(1,033)	4,526	9,805
Other comprehensive income before tax	1,057	(1,033)	4,526	9,805
Income tax expense (benefit) related to items of other comprehensive income	435	(413)	1,863	4,033
Other comprehensive income (loss)	622	(620)	2,663	5,772
Reclassification adjustment for gains (losses) included in net earnings		(997)		1,043
Income tax expense (benefit) related to reclassification adjustment		413		(412)
Reclassification adjustment for gains (losses) included in net earnings, net of tax		(584)		631
Other comprehensive income (loss), net of tax	622	(1,204)	2,663	6,403
Total comprehensive income	$ 10,202	$ 7,854	$ 27,972	$ 23,189

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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